1. Field of the Invention
The present invention relates to a switch device for operating several kinds of appliances which are installed in a motor vehicle serving as a moving body.
2. Field of the Invention
The motor vehicle serving as a moving body incorporates several kinds of appliances such as a car radio and a car navigation system. These appliances each is equipped with plural operation switches and dial switches.
Further, the steering column of the motor vehicle is generally equipped with a lever switch for operating several kinds of appliances such as an illumination device, wiper device and blinker.
Such a lever includes a shaft body with its stem attached to a steering column and an operating body which is retractable or rotatable on the shaft body. The shaft body of the conventional lever switch is formed to have such a length that its tip is located on the outer periphery of the ring of the steering wheel.
Where the operating body is rotatable on the shaft body, the rotating operation was given a sense of click by a well known clicking mechanism. In this case, the operating body is urged by a relatively strong force so that its displacement on the shaft body in a rotating direction correctly indicates the position at the present time. Therefore, a driver was required to grasp the operating body by a relatively strong force and thereafter rotate the operating body.
When the driver intends to operate several kinds of switches for the car radio or navigation system, he must once shift his viewpoint from the state of looking ahead of a vehicle to that of looking at the several kinds of switches. In addition, he must once cease to grasp the steering wheel and operate the various switches. The operability of the appliances was difficult.
In view of the difficulties of the conventional lever switches, an object of the invention is to provide a switch device capable of facilitating the operability of various appliances.
In order to attain the above object, in accordance with the invention, there is provided a switch device attached to a steering column which rotatably supports a steering wheel for a vehicle composed of a boss, a ring located around it and a coupling member for coupling the boss and the ring, comprising:
an operating shaft attached to the steering column;
an operating body attached to the operating shaft so that it is retractable from and rotatable around the operating shaft, wherein the entire length of the operating shaft is shorter than a distance from the hub to an outer edge of the ring.
In this configuration, since the entire length of the operating shaft is shorter than a distance from the hub to an outer edge of the ring, a driver can operate the operating body while holding the steering wheel ring.
Preferably, the entire length of the operating shaft is set so that its tip is located between the outer edge and inner edge of the ring in a radial direction of the steering wheel ring.
In this configuration, the driver can operate the operating body more surely while holding the steering wheel ring.
Preferably, the operating body is formed in a cylindrical form and arranged coaxially with the operating shaft, and provided around the operating shaft so as to be rotatable in directions opposite to each other.
In this configuration, the operating body can be used to adjust the quantity of status such as sound volume of a car radio that is successive with no step. Further, the driver can exchange the function of the appliance according to the rotating angle of the operating body.
Preferably, the operating body includes an attaching member rotatably attached to the operating shaft and an operating portion extending from the attaching member along the operating shaft, a frame member is provided which is attached to the operating shaft and has a supporting member for supporting the operating member, and the operating body is made of synthetic resin having a low friction coefficient between the operating shaft and the attaching member and between the supporting portion of the frame member and the operating portion.
In this configuration, the driver can operate the operating body more surely while holding the steering wheel ring.
Preferably, the operating body is made of synthetic resin having a low friction coefficient between the operating shaft and the attaching member and between the supporting portion of the frame member and the operating portion.
In this configuration, the operating body can be rotated around the operating shaft by relatively small operating force.
Preferably, the operating shaft is arranged along the coupling portion. Therefore, the driver can operate the operating body more surely while holding the steering wheel ring.
The above and other objects and features of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings.